title: Warranty period of normal stress myocardial perfusion imaging in diabetic patients: a propensity score analysis.
abstract: BACKGROUND
  We evaluated the relationship between diabetes and temporal characteristics of cardiac risk at long-term follow-up in a propensity score-matched cohort of diabetic and non-diabetic patients with normal stress myocardial perfusion single-photon emission computed tomography (MPS).
  
  
  RESULTS
  We studied 828 consecutive patients with suspected or known coronary artery disease and normal perfusion at stress MPS. To account for differences in baseline characteristics between diabetics and non-diabetics, we created a propensity score-matched cohort considering clinical variables and stress type. After matching, clinical characteristics were comparable in 260 diabetic and 260 non-diabetic patients. All patients were followed for at least 1 year (median 53 months). End-point events were cardiac death or nonfatal myocardial infarction. At Cox analysis, diabetes (hazard ratio 3.9, P < .01) and post-stress left ventricular ejection fraction (LVEF) ≤45% (hazard ratio 4.1, P < .01) were independent predictors of events. At parametric analysis, non-diabetic patients with post-stress LVEF >45% remained at low risk for the entire length of follow-up, while the highest probability of events and the major risk acceleration was observed in patients with diabetes and post-stress LVEF ≤45%.
  
  
  CONCLUSIONS
  After a normal stress MPS, diabetic patients are at higher risk for cardiac events than non-diabetic subjects also after balancing clinical characteristics and stress type by propensity score analysis. The warranty period of a normal stress MPS varies according to diabetic status and post-stress LVEF.
authors.affiliation: Institute of Biostructure and Bioimaging, National Council of Research, Naples, Italy.
authors.forename: Wanda
authors.initials: W
authors.lastname: Acampa
authors.forename: Mario
authors.initials: M
authors.lastname: Petretta
authors.forename: Renato
authors.initials: R
authors.lastname: Cuocolo
authors.forename: Stefania
authors.initials: S
authors.lastname: Daniele
authors.forename: Valeria
authors.initials: V
authors.lastname: Cantoni
authors.forename: Alberto
authors.initials: A
authors.lastname: Cuocolo
mesh_terms: D000368:Aged; D003324:Coronary Artery Disease / Q000150:complications* / Q000000981:diagnostic imaging*; D048909:Diabetes Complications / Q000000981:diagnostic imaging*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D010477:Perfusion; D011336:Probability; D011379:Prognosis; D057216:Propensity Score; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D016896:Treatment Outcome